Flotation machine



Dec. 27, 1938. HALL I 2,141,862

FLOTA'I ION MACHINE Filed Dec. 16, 1936 NVENTOR. mm 4m ATTORNEY.

Patented Dec. 27, 1938 UNITED STATES PATENT OFFICE- 4 Claims.

This invention relates to ore concentrating machines, and particularlythat type known as flotation machines.

The object of the present invention is generally to improve and simplifythe construction and operation of flotation machines; to provide amachine which is especially adapted for ore flotation concentrationprocesses in which air and a flotation agent, such as pine oil and otherchemicals, are introduced; to provide eiiicient means causing a thoroughdiffusion and mixing of the air and flotation agent with the pulp toproduce the greatest amount of froth possible; to provide means wherebyeflicient circulation and recirculation of the pulp and frothing agentare insured; to provide a machine of large capacity capable of handlingore pulps containing a small percentage of concentrates; and, further,to provide a machine in which power consumption and wear are reduced toa The flotation machine is shown by way of illustration in theaccompanying drawing, in

which- Fig. 1 is a central vertical section of the mag5 chine, taken online II of Fig. 3; 1

Fig. 2 is a cross section taken on line III[ of Fig. 3; and

Fig. 3 is a plan view of the machine.

Referring to the drawing in detail, and par 30 ticularly to Figs. 1 and2, A indicates in general a tank comprising a bottom section 2, sidewalls 3 and 4, and end walls 5 and 6. The tank is divided into twowells, generally indicated at B and C, by a cross-partition plate I. Thewell B 5 will hereinafter be referred to as "thecirculating well, andthe well C, as the settling and return 7 well.

Thewell B is, in this instance, rectangular in shape and has a housing Ddisposed in the bot- 4,0 tom thereof and extending lengthwise of themachine. The upper portion of the housing is provided with an opencylindrical discharge 7 member 8, while the opposite sides of thehousing are provided with ports 9 and III, which function as inletports. An air delivery pipe H extends under the bottom of the housing Dand is provided with a plurality of air-discharging nozzles l2 whichdirect air and pulp upwardly in the housing and through the outlet 8, aswill 50 hereinafter be described. v

Disposed above the outlet 8 is a rotary atomizing disk ll. 'This disk isof larger diameter than the outlet and may be constructed of metal,rubber, or other suitable material. The disk is a, suitably securedon-the lower end of a shaft ll journaled in bearings l6 and I1, and maybe driven by a pulley l8, or any other suitable means. I r

In actual practice, the ore pulp, together with the frothing agent oragents employed, is delivered to a feed trough 20 disposed at one sideof the well. The material moves downwardly and enters the bottom of thewell through a port 21, which is provided with a gate 22 adjustable fromthe top of the tank through a 10 screw rod and nut, as indicated at 23and 24, respectively. Air discharging from the nozzles l2 upwardlythrough the housing D and through the outlet 8 causes rapid elevationand discharge of the pulp through the outlet 8, and at the same 15' timebrings about circulation of the pulp in the tank as continuous dischargethrough the outlet 8 will cause continuous inflow through the lowerports 8 and ID.

The air jets serve two functions: First, that 0 of bringing about andmaintaining continuous circulation of the pulp, and, secondly, that ofintroducing the air required to bring about frothing. Actual frothing isproduced by the atomizing disk It, as this rotates at a suflicientlyhigh 25 speed centrifugally to project the air, together with the pulpdirected against the lower surface thereof, to cause substantiallycomplete atomization; and, further, to bring about such intimate mixingand breaking-up of the air and flotation agents carried by the pulp thatan-abundance of froth will be produced and will be uniformly distributedthroughout the pulp.

The froth thus produced, together with the enclosed or attachedconcentrates, rises to the surface 28 of the tank and overflows at thepoint 29, whilethe gangue settles in the well 0, to be returned andrecirculated a number of times before flnally discharging through port30 into an adjoining or similar unit.

Recirculation is important, as it gives the concentrates which are notfloated at first a second, third, or fourth chance before entering thenext unit or machine.

The discharge port 30 is also provided with an adjustable gate, such asshown at 3|, this gate being controlled by a screw rod and nut in amanner similar to the gate 22. An adjustable gate at the discharge sideis important as it regulates the velocity and thereby the sand level atthe bottom of the well. While pulp enters the housing D through both ofthe ports indicated at 9 and Hi, the. port 9 may be considered as themain intake port as it is closer to the feed I inlet, and also becausethe sand or gangue to be recirculated is directed thereto by slantingone of the sides of the well C, as indicated at 34.

In flotation concentrating machines, particularly of the type hereshown, swirling of the pulp should be prevented as much as possible, as

swirling and undue agitation at the surface where the froth is collectedare. detrimental. To prevent such swirling, due to the rotation of theatomizing disk l4, baflies, such as indicated at 35, or similar means,may be employed.

The machine shown in this instance is particularly intended for largecapacity operations where pulps containing comparatively smallpercentages of concentrates are to be treated. In machines of thischaracter, power consumption, wear and tear, etc., must be considered,as the cost of handling such ore pulps would otherwise be prohibitive.In the present instance, only one moving part is employed, to wit, theatomizing disk I4. This is also the only part which is subject to anynoticeable wear. In actual practice the disk has been made of rubber,and it has been found that the wear produced by abrasion is practicallyunnoticeable. The power consumption is exceedingly low, and efllcientoperation is insured due to the thorough manner in which the froth isproduced and circulation is maintained. In actual practice, a disk twofeet in diameter, rotated at approximately 800 R. P. M. has beenemployed. This gives a rim or peripheral speed of about five thousandfeet per minute, and no doubt is the reason for the high degree ofdiffusion and eflicient frothing actually obtained.

While this and other features of the present invention have been more orless specifically described, I- wish it understood that various changesin form and proportion may be resorted to within the scope of theappended claims. Similarly, I wish it understood that the materials andfinish of the several parts employed may be such as the experience andjudgment of the manufacturer may dictate or various uses may demand.

Having described my invention, what I claim and desire to secure byLetters Patent is- 1. In an apparatus of the character described, an orepulp receiving tank, a cross-partition therein dividing the tank into acirculating 'well and a settling well, a housing adjacent the bottom ofthe circulating wellhaving an inlet at the lower end and a submergedoutlet at the upper end, a plurality of air nozzles in the housing fordirecting air upwardly through the outlet of the housing to introducethe air required for frothing and to maintain continuous circulation ofthe ore pulp, a rotary disk disposed above the outlet centrifugally toproject and atomize matter directed against it by the outlet of thehousing, said disk causing the formation of a froth whereby concentratesin the ore pulp are floated t0 the surface of the circulating well andare caused to flow over to the setting well, means for directingmaterial from the settling Well back to the inlet of the housing forrecirculation, means for delivering pulp to be treated to a pointadjacent the inlet of the housing, and a gate-regulated submergeddischarge for control of the pulp discharging after treatment.

2. In an apparatus of the character described, an ore pulp receivingtank, means for delivering pulp to a point adjacent the bottom thereof,a housing disposed adjacent the bottom of the tank, said housing havingan inlet at the lower end and a submerged outlet at the upper end, meansfor introducing air and for maintaining a continuous circulation of pulpupwardly through the outlet of the housing, a rotary disk disposed abovethe discharge of the housing centrifugally to project and atomize mattercoming in contact therewith, and means disposed above the disk to stopswirling movement of the pulp as it rises to the surface of the tank.

3. In an apparatus of the character described, an ore pulp receivingtank, an elongated housing on the bottom of the tank, said housinghaving a submerged discharge tube on top thereof and openings onopposite sides for the admission of pulp to the housing; means fordelivering the pulp to be treated to a point adjacent one of said sideopenings, a pulp discharge port formed in the other side of the tankadjacent the other side opening in the housing, an air delivery pipeextending longitudinally of the housing and having a plurality ofair-discharging jets which direct air upwardly through the dischargetube to cause the pulp to enter the side openings in the housing and todischarge upwardly through the discharge tube, a rotary disc disposedabove the discharge tube of the housing to centrifugally project andatomize matter coming in contact therewith, means for removingmineralbearing froth from the surface of the tank, and means fordirecting settling pulp to the intake opening in the housing which isadjacent the feed inlet of the pulp, so as to cause recirculation of thepulp.

4. In an apparatus of the character described a rectangularly-shaped orepulp receiving tank, a cross-partition therein dividing the tank into acirculating well and a settling well, a housing in the bottom of thecirculating well having a submerged inlet and a submerged outlet, aplurality of air nozzles in the housing for directing air upwardlythrough the outlet to introduce the air required for frothing, and tomaintain continuous circulation of the ore pulp, a rotary disc disposedabove the outlet, centrifugally to project and atomize matter directedagainst it by the outlet of the housing, said disc causing the formationof a froth whereby concentrates in the ore pulp are floated to thesurface of the circulating well and are caused to flow over to the settling well, a slanting bottom in the settling well for directingsettling pulp back to the inlet of the housing for recirculation, meansfor delivering pulp to be treated to a point adjacent the inlet of thehousing, and a gate-regulated discharge port formed in the tank inalignment with the opening of the housing, to control the pulpdischarging after treatment.

ROBERT G. HAIL.

